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Build help and troubleshooting => CP5176 FET compressor => Topic started by: Trisonic on April 06, 2024, 06:18:22 AM

Title: GR Meter not lighting up, D8 and D16 LED shows a short between pads
Post by: Trisonic on April 06, 2024, 06:18:22 AM

Hello,

I've completed the build on my CP5176 kit and I was able to complete most of the setup steps, however on the GR meter setup I was not able to get any of the lights to light up while turning P7.

I checked all the Diodes with my multi-meter and all of them lit up except D8 and D16.  Multi-meter screamed at me and told me they were shorted.

I removed the D16 diode and it lit up as expected with the multi-meter.  The pads themselves on the board are showing a short.

As far as I can tell from the schematic, the only thing between the pads are the ICs... did I get a few duds?

Title: Re: GR Meter not lighting up, D8 and D16 LED shows a short between pads
Post by: JPK on April 06, 2024, 04:35:33 PM

Look for solder bridges or reversed IC's.
If the issue was in U4, the LED's 1 to 8 should work.
Check that you get the power voltages on the IC's pin3 (+15V) and pin12 (-15V).
Check that you get some control voltage on pin 5, 7, 9, 11 of the 4 IC's.

Title: Re: GR Meter not lighting up, D8 and D16 LED shows a short between pads
Post by: Trisonic on April 07, 2024, 07:42:23 AM

Whelp, I'm just an idiot and managed to flip literally every LED around the wrong way 🥴

I'm still very confused why some of the pads are reading a short, but I've swapped around all the LEDs with new ones and everything is working.

Sorry for the... very dumb error.  At least now I'm very familiar with how this part of the circuit works...

Title: Re: GR Meter not lighting up, D8 and D16 LED shows a short between pads
Post by: JPK on April 08, 2024, 12:19:34 PM

(https://fonts.gstatic.com/s/e/notoemoji/15.0/1f44d/32.png)